rods and cones

n=2

Or Maybe Satellite Dishes?

a: rods and cones ~

b: antennas on old TV sets

What:

"The rods and cones are like antennas on old TV sets, and if these antennas are broken, you don't get a good picture on the TV," he explained. "So if enough rods and cones degenerate, then vision quality and center vision goes down."

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